I looked up the exact quote I had in mind:
Denethor : "But in desperate hours gentleness may be repaid with death."
"So be it," said Faramir.
"So be it!" cried Denethor. "But not with your death only, Lord Faramir: with the death also of your father, and of all your people, whom it is your part to protect now that Boromir is gone."
I hope that was the right one!?

I'll need some more time to think out a new quote (and to decide in which language...) though I am very busy these days, so I beg you to be patient.